1 Features
- Low Standby-Current Consumption of 10 μA Max
- I2C to Parallel-Port Expander
- Open-Drain Interrupt Output
- Compatible With Most Microcontrollers
- Latched Outputs With High-Current Drive Capability for Directly Driving LEDs
- Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
2 Applications
- Telecom Shelters: Filter Units
- Servers
- Routers (Telecom Switching Equipment)
- Personal Computers
- Personal Electronics
- Industrial Automation
- Products with GPIO-Limited Processors
3 Description
This 8-bit input/output (I/O) expander for the two-line bidirectional bus (I2C) is designed for 2.5-V to 6-V VCC operation.
The PCF8574A device provides general-purpose remote I/O expansion for most microcontroller families via the I2C interface [serial clock (SCL), serial data (SDA)].
The device features an 8-bit quasi-bidirectional I/O port (P0–P7), including latched outputs with high-current drive capability for directly driving LEDs. Each quasi-bidirectional I/O can be used as an input or output without the use of a data-direction control signal. At power on, the I/Os are high. In this mode, only a current source to VCC is active.
Device Information
| PCF8574A | VQFN (20) | 4.50 mm × 3.50 mm |
| PDIP (16) | 19.30 mm × 6.35 mm | |
| SOIC (16) | 10.30 mm × 7.50 mm | |
| TSSOP (20) | 6.50 mm × 4.40 mm | |
| TVSOP (20) | 5.00 mm × 4.40 mm |
(1) For all available packages, see the orderable addendum at the end of the data sheet.
